Receiver for high-frequency electrical oscillations.



s -P. K. VREELAND. v RECEIVER FOR HIGH FREQUENCY ELEGTRIGAL'OSGILLATIONS. 7 APPLICATION FILED JULY 25, 1905. 930,50 Patented Aug. 10, 1909.

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I i r i' i s 4+ flit-m i ;1 i :5 i H 2H 'I i g Y s/ i r L v Witnesses: v 4 Inventor P. K. VREBLAND. RECEIVER FOR HIGH FREQUENCY ELECTRICAL OSCILLATIONS.

APPLICAIION FILED JULY 25, 1905. 930,508

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Witnesses ill FREDERICK K. VREELAND, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO WIRELESS TEL-E- GRAPH EXPLOITATION COMPANY, OF NEW YORK, Y. A CORPORATION OF NEW YORK.

RECEIVER FOB HIGH-FREQUENCY ELECTRICAL OSCILLATIONS.

Specification of Letters Application filed July 25, 2905.

Patent-ed .aa -I 10, lane.

Serial No. 271,203.

energy of high frequency alternating currents directly, without the use of any intern'iediate translating device, to produce me chamcal movement, but particularly to utilize the high frequency currents which are up in a wireless telegraph receiving apparatus to produce anaudible' signal or to operate a relay'or other receiving apparatus involving mechanical movement. This result is accomplished by means oftwo coils wound in close inductive relation, so that their mutual induction is nearly as great as the self-induction of each, and traversed by the rapidly alternating signal impulses in opposite directions, so that their respective magnetic fields are mutually opposed, and the mutual induction of the two coils practically neutralizes their self-induction. T he coils are connected in parallel in the receiver ,circuit, and the mechanical action between them will'be a force of repulsion. This force may be utilized to produce an audible signal by mounting one or each of the coils on an elastic diaphragm of insulating material, such as thin glass, and mounting this diaphragm, after the fashion of an. ordinary telephone receiver, in the capsule which is applied to the ear; or one coil may be ii: ed and the other movable about an axis, the movable coil being caused to opemand close a pair of contacts and thus operate a telegraph sounder or other receiving device; or two movable coils may be mounted on the same axis, and a pair of similar fixed coils be arranged one opposite each of the movable coils. ln winding thecoils I prefer to wind them spirally in dislr form. lo this form the coils may be placed face to face and close to ether so that they shall have a large mutual induction. it is desirable that the two coils be geometrically similar, 2'. e. that each turn of one coil shall be placed close to a similar turn of the other coil, so that the self-induction not only of the Whole coils, but of each individual turn of these coils, shall be directly neutralized by the mutual induction, thus dolng away with the reflections and other disturbing effects which occur when a high frequency current encounters an unbalanced inductance- To secure for "a given space the-maximum number of turns and maximum conductivity in a single layerof the conductor, I prefer to make each coil of a thin metallic ribbon suitably insulated and wound spirally flatwise upon itself, the width of the ribbon constituting the thickness of the coil.

Iii, the dra Wing, Figure l is a diagram show-- ing an arrangement of two opposed coils; Fig. :2 is a diagram showing an arrangement of four coils; F is a cross-section of one of the coils made of an insulated metallic ribbon; Fig. l is a sectional view of a re-- ceiver, showing a movable and fixed coil mounted in a telephone-receiver capsule, the movable coil being carried by a diaphragm; Fig. '5 is a sectional view of a receiver where in both coils are mounted upon diaphragms; l ig. (i is a plan view showing four coils, two movable and two fixed, the movable coils be ing carried by a frame carried by. oppositely strained spiral sprincs: and ,liig'. T is an elevation showing the t'rahiccarrying the two movable coils suspended by torsion wires. p I

In Fig. l the two spirally wound coils T, 8 are wound in opposite directions and connected in parallel, the center turn of each coil being shown connected to the receiving antenna A, and the outer turn of each coil to the ground plate G. l prefer that each coil should be made of an insulated metallic ribbon wound spirally tlatwise upon itself, as shown in Fig. 3. One of these coils may be mounted on a telephone diaphragm 9 of glassor other elastic insulating material, and the other be fixed on the body of a rolephone-receiver capsule 10, as shown in Fig. l; or both. coils may be mounted on similar diaphragms 11, 12 in a suitable case 13, inclosing between them an air space opening into an ear piece, as shown in Fig.

Fig. 2 shows two sets of coils arranged to form a relay, the two fixed coils ll, 15 being connected in series, and the two movable coils 16, 17 being also connected in series, and the two pairs of coils being connected in parallel between the antenna and groun i. it is desirable to have the current enter the system through the middle turns of one pair of coils ll, 16, and leave through the middle turns of the second pair 15, 17. The movable coils may be mounted by a suspension of any one of several well known types, for example through a -pair of mutually opposed spiral springs which ,serve to carry the current into and out of the movable coils, as shown in Fig. 6, or by a double suspension of torsion wires which serve a-similar purpose, as inFig. 7. In Fig. 6 the local circuit is shown including the sounder 18 and local battery 19.

Although a receiver of this typemay be used in connection with a spark transmitter of the ordinary well known form, which gives off strongly damped Wave trains of short duration separated by long intervals of inactivity, "it is much more effective and is particularly intended for use in connection with a transmitter which produces undamped or at least long-sustained oscillations, such asis set forth in my application for Letters Patent filed February 28, 1905, Serial No. 247826 (Patent No. 829 147 dated August 28, 1906), in which case the receiving circuit in which the receiver is placed or with which it is connected, hich receiving circuit is preferably a tune circuit, carries'signal impulses composed of undamped or sustained high frequency electrical oscillations. The advantage of. a persistent signal of this character arises from the fact that a receiver of the form herein described is cumulative in its action, and a very considerable time, compared to the frequency of the oscillations, is required to set the movable coil in motion,however lightly this coil may be constructed. A receiver of this type, used in connection with a transmitter emit-- ting undamped radiations, is capable of accumulating enough energy from a prolonged signal impulse to produce a noticeable efi'ect even though the intensity of the radiationsbe very small. It is possible to operate a system of this character by signals which would not affect a receiver of the .ordinary well known type whose indications depend upon the intensity of the signal impulses rather than on the total energy.

Although my receiver is shown as con-- use in connection with a tuned receiving.

circuit of any one of the well known forms for syntonic signaling, although it may be used in a simple responsive system. On account of its low resistance and low effective inductance, the receiver is well suited for use in connection with the current multiplier described-at page 200 of my book published in 190-4 on Maxwells theory and wireless telegraphy W hat I claim is:

1. A receiver for high frequency signal impulses wherein are combined two relatively movable coils arranged in close inductive relation with their magnetic fields mutually opposed, such coils being connected in parallel, substantially as set forth.

2. A receiver for high frequency signal impulses wherein are combined two relatively movable and geometrically similar coils arranged in close inductive relation with their magnetic fields mutually opposed, such coils being connected in parallel,substantially, as set forth.

This specification signed and witnessed this 17th dayof July, 1905.

FREDERICK K. VRE E LAND.

lVitnesses J NO R-OBT. TAYLoR, JOHN S. Lorsorr. 

